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Rotate Symbols to Graticule

November 30 2008 | 0 comments
Categories: Cartographic Effects, Symbology

Have searched around and can't find any way to rotate point symbols to the map graticule. We are after this for square symbols we are using for capitals in an atlas.

Preferably I'd like this to be a dynamic rotation as we are using a single WGS84 dataset but projecting on the fly to different map projections, but my other thought was to have a temp field called something like GratRotation which could be calculated each time a map is run. In this case I guess a script would be needed which could obtain latitude page angles for a point feature class.

I suppose I could also use labels to create the points but I would rather do this via the points symbolgy.

Does anything like this exist or do you know of any other way to go about this?

Mapping Center Answer:

Ah, the old square point on a round map problem...

Here's a trick (if your marker symbols are single layer and are character markers):

Set up the symbolized point layer in a WGS84 data frame.  Then use the Feature Outline Masks tool to create polygons of your markers.  Set the margin to 0; that way you'll get the exact extent.  Then project this dataset to your map's projection.

If your markers are multi-layer (multiple colors) you would need to create layers for each symbol layer and use the Feature Outline Masks tool.  This is a little more work, but it will work.

The only drawback (beyond the extra processing) is these will be a bit slower to draw, but if you're using relatively simple marker geometry, e.g., squares and triangles, it should be negligible.

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